Dissertations / Theses on the topic 'Linear encoders'
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Boyd, Phillip L. "Recovery of unknown constraint length and encoder polynomials for rate 1/2 linear convolutional encoders." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1999. http://handle.dtic.mil/100.2/ADA375935.
Full text"December 1999". Thesis advisor(s): Clark Robertson, Tri Ha, Ray Ramey. Includes bibliographical references (p. 79). Also available online.
Balák, Pavel. "Konstrukce otočného lineárně přesuvného stolu s pevnou boční upínací deskou pro stroj FGU RT." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230818.
Full textRosenfeld, Carl. "Automatiserad provrörskarusell : Elektronikkonstruktion och utvärdering." Thesis, Uppsala University, Signals and Systems Group, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-131153.
Full textDen här rapporten beskriver arbetet med en automatiserad provrörsförflyttare. Det är ett examensarbete som har gjorts på företaget Q-linea AB. En karuselliknande konstruktion med en stegmotor användes för att flytta prover mellan ett antal positioner. En mikrokontroller som hanterar styrning och sensordata har programmerats i C. LabVIEW och en USB-kamera har använts som hjälp till att göra utvärderingar och tester av systemet. Målet var att konstruera en prototyp som uppfyllde de precisionskrav och tidskrav som ställdes, vilket också uppnåddes. Rapporten beskriver arbetsgången och avslutas med rekommendationer för fortsatt arbete. Rapporten innehåller en teoridel som kan användas till hjälp för att konstruera liknande system, d.v.s. roterande positioneringstillämpningar.
This thesis describes the work of an automated sample tube mover. This is a degree project and has been done at the company Q-linea AB. A carousel similar construction with a stepper motor has been designed for the task to move samples between a numbers of positions. A microcontroller has been programmed to control the movements and handle sensor data. LabVIEW have been used together with an USB-camera in order to do evaluations and tests of the system. The goal was to design a prototype that fulfills the demanded requirements of precision and timing, which also was achieved. The thesis describes the work process and concludes with recommendations for further work.
Lee, Kwan Yee. "Analysis-by-synthesis linear predictive coding." Thesis, University of Surrey, 1990. http://epubs.surrey.ac.uk/844188/.
Full textGuan, Jun [Verfasser], and Rainer [Akademischer Betreuer] Tutsch. "Interferometric Encoder for Linear Displacement Metrology / Jun Guan ; Betreuer: Rainer Tutsch." Braunschweig : Technische Universität Braunschweig, 2013. http://d-nb.info/1175822043/34.
Full textDostál, Martin. "Konstrukční návrh lineární osy pro multifunkční obráběcí centrum." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443239.
Full textKarpf, Sebastian. "A system for time-encoded non-linear spectroscopy and microscopy." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-183458.
Full textRamanstreuung kann in der biomedizinischen Bildgebung dazu eingesetzt werden, Moleküle in einer Probe zu identifizieren, ohne dass die Probe vorher aufbereitet werden muss. Raman Mikroskopie kann funktionelle Bereiche sichtbar machen, indem es einen molekularen Kontrast auf Größenordnungen der Zellen bereitstellt und wird damit hochinteressant für die Krankheitserkennung in biomedizinischer Bildgebung. Der zugrundeliegende Raman Streuprozess ist ein optisch-inelastischer Streuungsmechanismus der die Detektion von Molekülschwingungen ermöglicht. Dabei wird das gestreute Licht detektiert und die Energiedifferenz zum Anregungslicht entspricht der molekularen Schwingungsenergie. Durch diese molekülspezifischen Schwingungsenergien ist es möglich, die Moleküle zu identifizieren und weiterhin durch die Signalhöhe zu quantifizieren. Diese Technik ist seit nunmehr beinahe einem Jahrhundert bekannt und findet breite Anwendung in Gebieten wie der Biologie, Chemie und der Medizin. Das Problem der Ramanstreuung ist die geringe Signalstärke des Effekts, wobei normalerweise nur eines von einer Milliarde Photonen gestreut wird. Es ist jedoch möglich, diesen Effekt durch nichtlineare Techniken um einige Größenordnungen zu verstärken. Dies wird besonders relevant beim Einsatz in der biomedizinischen Bildgebung von hochstreuendem Gewebe und bei hochauflösender Spektroskopie, wo gewöhnliche, gitterbasierte Spektrometer an ihre Grenzen stoßen. In der vorliegenden Arbeit wird ein neues System zur stimulierten Ramanstreuung (SRS) und hyperspektralen Ramanmikroskopie mittels eines schnell wellenlängenabstimmbaren Lasers vorgestellt. Hierfür wurde eine neue, zeitkodierte (TICO) Technik entwickelt, die es ermöglicht, die abgefragte Raman-Schwingungsenergie in der Zeit zu kodieren und weiter die durch SRS auftretende Leistungssteigerung direkt in der Zeitdomäne aufzunehmen, indem sehr schnelle Analog-zu-Digital-Wandler (ADC) mit 1.8 Gigasamples/s eingesetzt werden. Der hierfür entwickelte Pumplaser ist ein faserbasierter Masteroszillator Leistungsverstärker (MOPA) mit integriertem Ramanwandler, der einen Betrieb bei 1064 nm, 1122 nm oder 1186 nm ermöglicht. Diese Mehrwellenlängenfähigkeit basiert auf dem Ramaneffekt in der Glasfaser, der durch ein Keimlicht einer 1122 nm Laserdiode stimuliert wird. Überraschenderweise wurde dadurch ebenfalls ein schmalbandiger Betrieb (0,4 cm-1) der kaskadierten Ramanbanden bei 1186 nm und 1257 nm beobachtet, was zunächst der erwarteten breitbandigen Ramanbande von Glas widerspricht. Diese Ergebnisse wurden untersucht und es wird ein Modell vorgeschlagen, wonach der gefundene Effekt auf einer Kombination von Vier-Wellen-Mischen und kaskadierter Ramanstreuung beruht. Das schmalbandige kaskadierte Ramanlicht bei 1186 nm wurde im Experiment für hochauflösende Ramanspektroskopie von Benzol benutzt. Als Raman Stokeslaser wurde ein schnell wellenlängenabstimmbarer Fourierdomänen modengekoppelter (FDML) Laser benutzt, der einige Vorteile kombiniert. Als wichtigste Vorteile dieses faserbasierten Lasers sind die breite Abdeckung relevanter Ramanenergien, die sich von möglichen 250 cm-1 bis 3150 cm-1 erstreckt, die gleichzeitig hohe spektrale Auflösung (0.5 cm-1), und der für biologische Bildgebung interessante Dauerstrich-Betrieb (CW) zu nennen. Weiterhin wurde eine neue, zweistufig balanzierte Detektion entwickelt, die SRS Messungen an der Schrotrauschgrenze ermöglichen. Die wohldefinierte Wellenlängen-zu-Zeit Beziehung dieses Lasers wurde darüber hinaus dafür benutzt, den TICO-Raman Spektren direkt Ramanenergien zuzuweisen. Dadurch wurden hochqualitative Ramanspektren mit akkurater Wellenzahlinformation möglich. Das entwickelte System wurde für Anwendungen in der Raman Spektroskopie und nicht-linearen Bildgebung eingesetzt. Als Ergebnisse werden breitbandig abgetastete Ramanspektren präsentiert, die mit spontanen Raman Spektren verglichen werden. Weitere, neue spektrale Anwendungen wurden untersucht und erste Mikroskopiebilder erzeugt. Hierfür wurde die Probe mittels eines Verschiebetisches verfahren und an jedem Pixel ein TICO-Raman Spektrum aufgenommen. Die so erzeugten hyperspektralen Raman Mikroskopiebilder wurden in farbig kodierte Bilder mit molekularem Kontrast umgewandelt. Es wird eine TICO-Raman Mikroskopieaufnahme von einem Pflanzenschnitt präsentiert. Das System erlaubt es ferner, durch den Einsatz des hochintensiven Pumplasers Bilder mit Mehrphotonenabsorption zu messen, indem zweiphotonenangeregte Fluoreszenzbildgebung (TPEF) angewandt wird. Zusammenfassend wird in dieser Arbeit die Entwicklung eines neuen Systems der Spektroskopie und nichtlinearen Bildgebung beschrieben und erste Messergebnisse präsentiert. Mit diesem System wird es möglich sein, viele verschiedene Bildgebungsverfahren zu verbinden. Darunter unter anderem Bildgebungsverfahren wie die optische Kohärenztomographie (OCT), Absorptionsspektroskopie, SRS, TPEF, Frequenzverdopplung (SHG) und Frequenzverdreifachung (THG) und Fluoreszenzlebenszeitmikroskopie (FLIM). Der wohl vielversprechendste Vorteil dieses Systems liegt in dem faserbasierten Design, welches es ermöglichen kann dieses System zukünftig zur endoskopischen Bildgebung einzusetzen. Bereits jetzt ergibt dieser faserbasierte Aufbau ein sehr robustes System, das verlässlich, justagefrei und einfach zu bedienen ist.
Trnkócy, Tomáš. "Návrh a realizace testovacího zařízení manipulačního mechanismu vzorku pro elektronový mikroskop." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230625.
Full textShirley, Matt, and n/a. "Characterisation of an 84 kb linear plasmid that encodes DDE cometabolism in Terrabacter sp. strain DDE-1." University of Otago. Department of Microbiology & Immunology, 2006. http://adt.otago.ac.nz./public/adt-NZDU20060804.094902.
Full textOberhauser, Joseph Q. "Design, Construction, Control, and Analysis of Linear Delta Robot." Ohio University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1460045979.
Full textKarpf, Sebastian [Verfasser], and Robert [Akademischer Betreuer] Huber. "A system for time-encoded non-linear spectroscopy and microscopy / Sebastian Karpf. Betreuer: Robert Huber." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1073825930/34.
Full textGentilini, Lorenzo. "Kalman Filters: Linear and Nonlinear applications in Sensor Fusion." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Find full textBergenblad, Jonas. "Validation study of a portable accelerometer to measure muscular power output : Correlation between the Beast Sensor and the linear encoder MuscleLab." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34823.
Full textAbstrakt Bakgrund: Förmågan att producera hög effektutveckling (power) kan avgöra vilken idrottare som vinner eller förlorar en tävling. Effektutveckling kan mätas i övningar som knäböj och bänkpress. Detta kan göras med hjälp av en kraftplatta, eller en kraftplatta parad med en linear position transducer. Dessa metoder anses vara ”gold standard”, men linear position transducers eller linear encoders har också ansetts vara valida metoder. Effektutveckling kan även mätas med hjälp av en accelerometer. Syfte: Syftet med denna studie var att mäta samtidig validitet hos accelerometern Beast Sensor genom att mäta genomsnittlig effektutveckling i explosiva knäböj och bänkpressar vid 40 % och 80 % av en repetition max (1RM). MuscleLab, en linear encoder, användes som referensvärde. Metod: 17 försökspersoner, fem kvinnor och tolv män (medelålder 28 år) rekryterades. Femton av försökspersonerna fullföljde deltagande. Vid det första testtillfället mättes 1RM. Det andra tillfället ägde rum 7-14 dagar senare och mätte genomsnittlig effektutveckling i explosiva knäböj och bänkpressar vid 40 % och 80 % av försökspersonernas uppmätta 1RM. Två set av tre repetitioner mättes vid 40 % och 80 % av 1RM i både knäböj och bänkpress. Repetitionerna mättes samtidigt av MuscleLab och Beast Sensor. För att Beast Sensor skulle anses vara valid behövde en korrelationskoefficient på 0.9 eller högre uppnås. Resultat: Beast Sensor uppvisade höga eller väldigt höga korrelationer med MuscleLab för genomsnittlig effektutveckling i explosiva knäböj vid 40 % av 1RM (rs = 0.91) och explosiva bänkpressar vid 40 % (rs = 0.86) och 80 % av 1RM (rs = 0.74). Dock uppmättes en låg korrelation för de explosiva knäböjen vid 80 % av 1RM (rs = 0.42). Alla korrelationer var statistiskt signifikanta med p-värden på < 0.01. Beast Sensor ansågs vara valid för att mäta effektutveckling vid 40 % av 1RM i knäböj, men varken vid 80 % av 1RM i knäböj, eller vid 40 % eller 80 % av 1RM i bänkpressar. Slutsats: Beast Sensor visade höga eller väldigt höga korrelationer med referensvärdet från MuscleLab för tre av de fyra uppmätta variablerna. Endast korrelationen för genomsnittlig effektutveckling i explosiva knäböj vid 40 % av 1RM uppnådde den korrelationskoefficient på 0.9 eller högre som krävdes för att Beast Sensor skulle anses vara valid. Förutom vid 40 % av 1RM i knäböj, missade Beast Sensor en väsentlig andel repetitioner. Därför finns det ett behov av fler studier som undersöker reliabiliteten hos Beast Sensor.
Azad, Abul K. "Robust Speech Filter And Voice Encoder Parameter Estimation using the Phase-Phase Correlator." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/97221.
Full textDoctor of Philosophy
Impulsive noise is a natural phenomenon in everyday experience. Impulsive noise can be analogous to discontinuities or a drastic change in natural progressions of events. Specifically in this research the disrupting events can occur in signals such as speech, power transmission, stock market, communication systems, etc. Sudden power outage due to lighting, maintenance or other catastrophic events are some of the reasons why we may experience performance degradation in our electronic devices. Another example of impulsive noise is when we play an old damaged vinyl records, which results in annoying clicking sounds. At the time instance of each click, the true music or speech or simply the audible waveform is completely destroyed. Other examples of impulse noise is a sudden crash in the stock market; a sudden dive in the market can destroy the regression and future predictions. Unfortunately, in the presence of impulsive noise, classical methods methods are unable to filter out the impulse corruptions. The intended filtering objective of this dissertation is specific, but not limited, to speech signal processing. Specifically, research different filter model to determine the optimum method of eliminating impulsive noise in speech. Note, that the optimal filter model is different for time series signal model such as speech, stock market, power systems, etc. In our studies we have shown that our speech filter method outperforms the state of the art algorithms. Another major contribution of our research is in speech compression algorithm that is robust to impulse noise in speech. In digital signal processing, a compression method entails in representing the same signal with less data and yet convey the the same same message as the original signal. For example, human auditory system can produce sounds in the range of approximately 60 Hz and 3500 Hz, another word speech can occupy approximately 4000 Hz in frequency space. So the challenge is, can we compress speech in one of half of that space, or even less. This is a very attractive proposition because frequency space is limited but the wireless service providers desires to service as many users as possible without sacrificing quality and ultimately maximize the bottom line. Encoding impulse corrupted speech produces harsh quality of synthesized audio. We have shown if the encoding is done with the proposed method, synthesized audio quality is far superior to the sate of the art.
Björk, Julia. "The effect of a weight lifting belt and the use of valsalva maneuver on power output and velocity in a squat." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-33956.
Full textBakgrund: Det finns många olikheter i litteraturen när det gäller huruvida tyngdlyftarbältet påverkar prestationen och/eller om det minskar skaderisken. En knäböj är en vanlig övning som används inom många områden av styrketräning och för olika ändamål. Användning av andningstekniker är vanligt vid tunga lyft och därför kan utförandet av andningstekniken; valsalvamanövern vara av intresse att studera och om det tillsammans med lyftbältet kan ge effekt på effektutveckling och hastighet i lyft. Syfte: Syftet med studien var att utvärdera hastigheten i en knäböjs olika faser (excentriska, koncentriska och topphastigheten i den koncentriska fasen) och hur effektutvecklingen påverkas av lyftarbälte och valsalvamanövern. Metod: Femton personer (10 män och 5 kvinnor) deltog frivilligt och utförde totalt 12 knäböj i fyra olika sets med tre repetitioner på 75 % av testpersonernas självrapporterade 1RM. De första två seten var utförda antingen med eller utan tyngdlyftarbälte och de tredje och fjärde seten var utförda antingen med eller utan utövande av valsalvamanövern. Dessa tre förhållanden ( med lyftarbälte, med lyftarbälte + VA och VA endast) jämfördes med varandra och med kontrollgruppen ( ingen VM och inget lyftarbälte) med avseende på effektutveckling och hastigheten i den excentriska, koncentriska och topphastighet i knäböjens koncentriska fas. Resultat: Effektutvecklingen gav ingen signifikant skillnad i någon av de fyra olika förutsättningarna (med lyftarbälte, utan lyftarbälte, med bälte och valsalvamanövern och utan bälte och valsalvamanövern). Hastigheten i den excentriska, koncentriska och topphastigheten i den koncentriska fasen visade ingen signifikant skillnad mellan de fyra olika seten. Konklusion: Studien visade ingen skillnad vilket kan jämföras med tidigare litteratur där en skillnad fanns. Lyftarbältet och utförandet av valsalva manövern påverkade inte effektutvecklingen och/eller hastigheten när en knäböj utfördes.
Malmlöf, Erik, and Ola Scholander. "Reglering av veka strukturer med multipla sensorer." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1640.
Full textIn this master thesis, control algoritms using arm side sensors are investigated for an industrial robot. The sensors can be position encoders placed after the gearbox and accelerometers on the robot arms. Control strategies are discussed and evaluated for different models of the robot, after which chosen strategies are applied to a realistic model.
Control algoritms using arm side sensors (LQ, dual-loop and PD-PID) are compared to a PID-controller that only uses measurements of motor position for feedback control. The comparison are done with respect to disturbance rejection, oscillation damping, robustness and tracking performance of a reference trajectory.
Results from tests with the realistic robot modell shows that disturbance rejection was improved a factor 2 to 5 while tracking performance was improved a factor 4 to 5 according to maximum deviation from the reference path. At the same time good re-sults are achieved regarding oscillation damping and robustness.
Olovsson, Ståhl Elias, and Pontus Öhrner. "Concurrent validity of an inertial sensor for measuring muscle mechanical properties." Thesis, Umeå universitet, Avdelningen för idrottsmedicin, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-173423.
Full textFryčová, Martina. "konstrukční návrh stroje pro řezání laserem a plasmou." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230061.
Full textBonicalzi, Marie-Eve. "Role of Exon 2-Encoded ß-Domain of the von Hippel-Lindau tumor supressor protein." Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9314.
Full textSchmidt, Robert J. M. "Using Weighted Set Cover to Identify Biologically Significant Motifs." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1447797982.
Full textPavelec, Jiří. "Vývoj lineárního posuvu pro UHV STM/AFM." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2011. http://www.nusl.cz/ntk/nusl-229812.
Full textŠtibraný, Miroslav. "Řízený laboratorní zdroj." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-240809.
Full textLin, Chih-Chuan, and 林志全. "Wave form Research of Electrical Linear Encoder." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/31472581503086323731.
Full text國立中央大學
機械工程研究所
91
The new type of Linear Encoder. The new encoder decrease the disadvantage of other linear encoder. We use new sensor to sense the magnetic field which is generated by PCB. This paper research the wave form of Electrical Linear Encoder. Hope to find the most fit of PCB and MR sensors to get the best signal to encode.
Chen, Shih-Jui, and 陳世叡. "Design and Experiment of Linear Diffractive Laser Encoder Systems." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/05828730185827101976.
Full text國立臺灣大學
應用力學研究所
90
In this dissertation a compact size linear diffractive laser encoder was designed and fabricated. In addition, a step-by-step alignment procedure was also accomplished. This newly developed laser encoder used a 780 nm wavelength laser diode as the light source and was composed of several sub-systems, which include a 1-x telescope, a diffractive grating scale, and a circular polarization interferometer. The circular polarization interferometer sub-system can decode the optical interference signals obtained from two twice diffracted beams, both of which has their frequency subjected to Doppler shifted due to grating scale displacement. With the compact mechanical design and the isothermal design arrived from the common base plate, this newly developed laser encoder is less sensitive to environmental disturbances. As this laser encoder retrieves the grating scale displacement information from the pitch of the grating scale and not from the laser source wavelength, it was found to be potentially less prone to have its measurement accuracy influenced by the frequency drift of the light source used. The performance of the compact diffractive laser encoder system was verified by using the HP5529A interferometer as the measurement reference.
Jhong, Ze-Fu, and 鐘責夫. "Simulation of High Precision Capacitive Linear Encoder WithCOMSOL MULTIPHYSICS." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/84315522793065879149.
Full text國立雲林科技大學
機械工程系碩士班
94
COMSOL MULTIPHYSICS can use ( PDEs ) to describe various mathematical、physical engineering problem,or multiphysics problem,COMSOL MULTIPHYSICS is the CAE of using FEM to analyze problem. Rectangle fringe capacitive sensor,it is hard to derive the mathematical formula ,FEM can supply a solving method. In this paper,we use FEM analysis software─COMSOL MULTIPHYSICS to analyze the relation between capacitance and distance and can help designer to save time and cost in designing process.
Chen, Yung-yi, and 陳永益. "Design and Development of High Precision Capacitive Linear Encoder." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/76988833776519419016.
Full text國立雲林科技大學
機械工程系碩士班
93
Due to the demands of automatic industries and intelligent facilities are universal, it makes sensor systems to form a great quantity of using and captures a unique field in sciences and economies from its results. Unfortunately, it has been almost disappearing in national industries of high precision sensor systems and its demands must depend on import modes. For example, optical linear encoder which contains laser sources, optical detectors, circuits of signal processing and displays of measurements is complex and expensive, it confuses many industries with inventing. This research will introduce the key technologies in past investigations of the displacement sensor with sub-micron precision, the sensing circuit design and the signal processing algorithm to develop a capacitive linear encoder with low cost and high precision in the light of cost-saving on traditional optical linear encoder. The goal is to develop a capacitive linear encoder with the same precision of the optical linear encoder, 0.5μm, but at much lower cost.
LI, CHE-HSIEN, and 利哲賢. "Signal Drift of Linear Encoder Induced by Thermal Effect." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/xvdfn3.
Full text國立雲林科技大學
機械工程系
108
Linear encoder is widely used in the machinery industry. The detection unit of the linear encoder emerges the position signals through the relative displacement behavior the scale and the scanning reticle. However, the deformation of the machine and the linear encoder due to temperature drift results in an important influence on the precision machine. Traditionally, the thermal expansion effects are only investigated as static and steady state. However, for high-precision machine or measurement, the dynamic response of temperature drift must be discussed. The influence of thermal noise is also one of the important purposes in this study. Therefore, the Fabry-Perot interferometer to measure the change of the thermal expansion of the platform. Then utilized the result of the linear encoder and that of Fabry-Perot interferometer are compared to determine the relationship between the deformations and temperature drift. In order to inspect the deformation of the platform, three double-resonant cavity structures are designed in this study. Through the combination of different resonant cavity distances and different positions, the thermal expansion influence of platform can be obtained. That the displacements of the linear encoder with the platform at the positive limit, the middle and the negative limit are different, so that the linear encoder is affected by the temperature and the mechanism. There are different changes in different locations.
Li, Kun-I., and 李昆益. "The Analysis And Improvement of Electrical linear Encoder's Output Waveform." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/50044757368606776103.
Full text國立中央大學
機械工程研究所
92
The idea of an electrical linear encoder made in a brand-new way is to supply the industry with a low cost and high precision linear encoder. This paper has in mind from the principle of the electrical linear encoder— Biot and Savart’s Law, and starts from the principle of magneto-resistivity sensors—magneto-resistivity effect. Under the present frame of experiment, it not only finished redesigning the magneto-resistivity sensor’s circuit board, but also changed the mode of driving electrical linear encoder from the mode of pulse current to that of constant current. Successfully, it improved the resulting output waveform so that an electrical linear encoder takes one step ahead to achieve the dream of the industry standard’s application. In addition, this paper finished simulating the electrical linear encoder’s distribution of the magnetic flux, and analyzing some factors which have effects on the electrical linear encoder’s distribution of the magnetic flux as the later design references.
Hossein, Goudarzi Khouygani Mohammad, and 古達知. "Designing and Fabricating Optical Linear Encoder by Femtosecond Laser Direct Writing." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/ers68e.
Full text國立臺灣科技大學
機械工程系
106
This thesis is discussing fabricating and analyzing optical encoder. Two femtosecond lasers have been used for fabricating optimal and precise reflecting grating on the Invar alloy. Several gratings were made with different laser parameters in two regimes: constant repetition rates and constant average laser power. The efficiency of diffraction gratings is measured in an off-plane configuration by determining the power of diffracted points, image processing of Talbot image and also the pitch of gratings has been measured by an improved Littrow configuration setup. It has been shown that Talbot image setup has capability to be an online NDT test machine for grating in the optical encoder fabrication line. The method of improving Littrow pitch measuring setup could remove the error of installation up to 0.03º. An optical path has been introduced for making interference between orders of diffraction grating and according to this optical path, M-encoder has been designed and fabricated. The result of measurement in different traveling distances and in different installation situations has been showed that the total error of fabricating grating, installing error, environment, signal processing and circuits is less than ±195nm /100mm. The installation tolerance and size of M-encoder is compatible to the other encoders in the market.
Kuo, Fu-Yen, and 郭富彥. "Study on Vector-Sum Excited Linear Predictive Speech Coding: Encoder Improvement." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/56659936386543588677.
Full text國立交通大學
電子研究所
84
In wireless communication systems, a robust, low complexity and low bitrate speech coding algorithm is essential for voice applications. Vector-Sum excited linear predictive coding (VSELP) is one of the coding algorithms that can meet the requirement. We study the North American IS-54/136 VSELP speech coding algorithm and consider ways of encoder improvement in the sense of reducing complexity or improving speech quality. In terms of complexity reduction, several techniques are presented for longterm predictor search, excitation codebook search and gain quantization, which occupy more than 90% of encoding complexity. These methods respectively reduce roughly 6% to 20% of encoding complexity at moderateSSNR loss and can be applied to the encoder simultaneously. In terms of quality improvement, a tree-structured codebook search is considered. Roughly 0.3-1 dB SSNR improvement can be achieved by tree-search coding. We also present a technique which can significantly reduce tree-coding complexity. Moreover, we analyze simulation results to obtain rule-of-thumbformulas for determination of the various tree parameters under different complexity and performance conditions.
Teng, Hsin-Hao, and 鄧信豪. "A Novel Three-Degree-of-Freedom Diffraction Type Laser Linear Encoder." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/32x7w3.
Full text國立虎尾科技大學
光電與材料科技研究所
96
In this study, a three-degrees-of-freedom laser encoder was developed. The measuring principles of linear displacement measurement was based on the diffractive method and polarization interference method. The angle measuring method was the autocollimation method. These optical paths of these two methods are designed in a single optical system. The resolution of linear displacement is 13.1 nm and the angular resolution is 0.11 arcsec.The HP laser interferometer and an autocollimator were used to verify our proposed system. The accuracy of linear displacements is 160 nm and the accuracy of angular measurement is 0.41 arcsec.
-ju, shing, and 吳星助. "A Novel Diffraction Type Three-degree-of-Freedom Laser Linear Encoder." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/2b8fae.
Full text國立虎尾科技大學
光電與材料科技研究所
94
Encoders are widely used as the positioning sensors. If the encoders and moving axis not to match, it were produced ABBA error. Three-degree-of-Freedom Laser Linear Encoder based on diffraction and interference is presented. The displacement field is measured using a polarization interference technique and the angle is measured using a near-axis optical theorem. We have developed a laser linear encoder that can detect displacements relative to an external grating scale with residual error of 200 nm and can detect angle error relative to quadrant detectors measure with residual error of 0.4 arsec.
ZHAN, XIANG-AN, and 詹翔安. "Development of a Four-Degree-of- Freedom Common Path Linear Encoder." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/a5369s.
Full text國立臺灣科技大學
機械工程系
107
An innovative four-degree-of-freedom common path linear encoder with the ability to simultaneously measure both in and out of plane displacements and rotations is proposed in this study. This linear encoder combines the advantages of interferometry, grating interferometry, beam splitting techniques and common optical path design to develop a system with high sensitivity, high stability, high tolerance, precise displacement measurement and self-correction capability, and has been successfully miniaturized. The four-degree-of-freedom common path linear encoder has the advantages of simple configuration, quick set up and low cost. In addition, only one set of prism and grating is needed to obtain both in-plane and out-of-plane displacement information. The system is designed around the core of a common optical path configuration, focusing mainly on the angle of the prism. This causes the laser light source entering the prism to split into a transmission P beam and a refracted R beam. The P and R beam are then incident onto the optical scale (grating) at an oblique angle and diffracted, causing the diffracted P and R beams to overlap forming interference. When the grating is displaced in and in-plane or out-of-plane direction, the phase change of the interference signal received by a photodetector can be used to obtain the grating displacement value. To further enhance the measurement capability of this system, beam splitting was utilized to form two detection points on the grating, allowing the linear encoder system to measure displacement and rotation simultaneously, while compensating for measurement alignment errors, and give the system the ability to self-correct. The experimental results show that the resolution of the displacement and rotation angle of the four-degree-of-freedom common path linear optical scale can reach 10 nm and 200 nrad, respectively. The repetition rate can reach 3.6 nm and 71 nrad, and the stability is within 30 minutes. Under the condition of better than 30 nm and 1000 nrad, the speed limit can reach 8800 μm/s. It has excellent measurement performance and potential of commercial development, and can be widely used in various occasions where precision measurement is required.
CHEN, CHIEN-CHENG, and 陳建成. "Construction and display algorithms for linear octree encoded objects." Thesis, 1989. http://ndltd.ncl.edu.tw/handle/15539115930188161584.
Full textCHANG, EN-SHEN, and 張恩慎. "Speed Estimator Design with FPGA and Linear Encoder for the Application of Linear Shaft Motor Drive System Design." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/f4c3zh.
Full text國立勤益科技大學
電機工程系
107
Owing to the benefits of programmable and parallel processing of the field programmable gate arrays (FPGAs), they have been widely used to the realization of digital controllers and motor drive systems. In this study, we adopt the FPGA chip to realize the Linear Shaft Motor (LSM) drive system which includes the position control, speed control and current vector control. Linear shaft motor is a special motor which has the magnet as the shaft, and stator coils are on the forcer. Thus, it reveals a small mechanical time. In addition, the electrical side can be looked as a general three-phase AC system which can be powered by inverter, and field oriented control (FOC) technique can be applied to the system. The designed system needs high performance calculation ability about position/speed control and FOC-based current control loops. In this experiment, a comparison of speed control is made for the MT estimation algorithm and the general pulse difference speed estimation algorithm. The mathematical model of linear shaft motor drive system is first built and simulated by MATLAB/Simulink, and the correctness and performance of the hardware circuits are simulated and verified. After that, simulated model for both the MT method and pulse different plus moving average method are built, and their performance are practical implemented with the trapezoidal speed profile commands to evaluate the performances.
柯佳惠. "A chromosally encoded gene involved in maintenance of linear plasmids in Streptomyces." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/53283633292339948776.
Full text國立陽明大學
遺傳學研究所
90
The terminal regions of the linear Streptomyces chromosomes are highly unstable, undergoing spontaneous large deletions of up to 2 Mb. Several deletion mutants of S. lividans contained circularized chromosomes, and could not be transformed by the linear plasmid SLP2. This suggested that these deletions contained at least one gene involved in the maintenance of the linear plasmids (designated lpm for linear plasmid maintenance). Because linear Streptomyces plasmids have 5’ covalently bound terminal protein, it is believed that chromosally encoded terminal protein gene (tpgL) might play a vital role in linear plasmid maintenance. Since the Lpm+ and Lpm- strains were tpgL+ and tpgL- , respectively, complementation test was performed to determine if tpgL was lpm. Insertion of a 4.5-kb fragment contains tpgL inserted into the chromosome or a mini-linear plasmid restored the Lpm+ phenotype to Lpm- host, this indicates that the 4.5-kb fragment contains the lpm function.
Susanto, Misfa, Yim Fun Hu, and Prashant Pillai. "Joint random linear network coding and convolutional code with interleaving for multihop wireless network." 2013. http://hdl.handle.net/10454/9737.
Full textAbstract: Error control techniques are designed to ensure reliable data transfer over unreliable communication channels that are frequently subjected to channel errors. In this paper, the effect of applying a convolution code to the Scattered Random Network Coding (SRNC) scheme over a multi-hop wireless channel was studied. An interleaver was implemented for bit scattering in the SRNC with the purpose of dividing the encoded data into protected blocks and vulnerable blocks to achieve error diversity in one modulation symbol while randomising errored bits in both blocks. By combining the interleaver with the convolution encoder, the network decoder in the receiver would have enough number of correctly received network coded blocks to perform the decoding process efficiently. Extensive simulations were carried out to study the performance of three systems: 1) SRNC with convolutional encoding, 2) SRNC; and 3) A system without convolutional encoding nor interleaving. Simulation results in terms of block error rate for a 2-hop wireless transmission scenario over an Additive White Gaussian Noise (AWGN) channel were presented. Results showed that the system with interleaving and convolutional code achieved better performance with coding gain of at least 1.29 dB and 2.08 dB on average when the block error rate is 0.01 when compared with system II and system III respectively.